In what has been a regular pattern for Melbourne over the last couple of weeks, a spell of midweek warmth will be replaced by cooler conditions tomorrow, just in time for the weekend. Yesterday a large high pressure system that was settled over southeastern Australia brought a sunny and warm day to Melbourne. The mercury climbed to a toasty 27 degrees, which was seven above average. It was also a balmy night by recent standards, thanks to warm northerly winds pulling heat from the nation's interior over the city. During Thursday morning these northerlies became gusty, mixing this warm air towards the surface and keeping temperatures eight degrees above average. It only cooled to 17 degrees, which was the warmest night the city has had since March and no doubt warmly received by all. Thursday is also set to be a warm one. At 10am it had already warmed to 24 degrees, with the mercury likely to climb to 29 in the afternoon. The warmth is nearly over however. As a trough moves over the region this afternoon winds will tend southwesterly, bringing a cooler airmass over the city. This will lead to a cooler night and result in closer to average temperatures on Friday. It will be even cooler on the weekend as a cold front arrives, with tops of 16 degrees expected on both days and gusty showers making it feel extra nippy.